Telephone system



May 24, 1932. E. P. e. WRIGHT TELEPHONE SYSTEM Filed May 26, 1930 ESMOND RG. WRIGHT ATTORNEY NnK 3% p L @3 km be? Q E 6 1m q R 4 i 6 E Patented May 24, 1932' r v 'rE i' TAT nsnionp 2mm eoopwin WRIGHT, 0FALDWHQLQNDON amiss; Assam o 1 v m'i'nezmnoimt STAN RD EELEQTRICVCQBPQBATIQN, or nEwYasmin-,1

TELEBEQNE YS EM 7 a plication filed na"2s,is3o,-seria1 No. 4 5 5 ,636; an d G at-entail: ma s ng; p

This invention relates to semi-automatic telephone systemsand more particularly to circuit arrangementsassooiated with operators positions Wherebyidle' trunks ai allahle for use'may be indicated to the operator.

One feature of the invention eomprisesoin ouit arrangements 0% the type vdesorlbfed above, characterized in thi s that in; response to action on the part of the operator, an ndieation' is given individual to a trunk which has access to an idle conversational switch and which is assoc'iatedwith common apparap the key OKwill'he operated closing them:-

tns available-for use therewith. i

Further features will be apparent fromithe description and will beset out in the appended'elaims. One embodiment of'the'v invention will be described below, but it is to be understood N p k that the invention is not limited to the-said embodiment biltis capable of any variation which falls'within the scope ofany one of the appendedclaimsrjy a The" invention; is described with reference p to the accompanying drawings, Whioh shows cireilits at an opera-tors position for'testmg I LP, On pressing key OK, a switch R is caused to hunt for a trunk available for use which is determined by battery applied to,

a test conductor-such as BPT over the circuit ShO-WI} the Contacts aboiethe broken line The are individual to aeom'mon bye-pass oirciiit, as ooiated with h said trunk. Wh n an ava lable trunk is found the'switch is stopped,

lampQL lights and tens and ,un'itslamps 1n the bankLP are 'lightedfto indicate the said trunk. The test conductor Hof thetrunk is rth dto mark hem-fin e bank o abye-pass. switeh R a d when, aft r t e bye.-

pass has en se by the d alledidigit o digits; f

' ing key CK; v

idem of a conversational siWi-toh and whys;

ing'individual-to a trunk and its conversa' -i tional switch Whilethose below the said line the said b es-pa h iff fi the a. holding circuit over rfthe' eondfiotor BPT is removed and the lamps release; By' throw; ing one "of the "group keys, silt/h as oi' -B' in co junct on with key OK; a trunk having outlets in a Wanted direction isfound lfien indicated tiiurik 'is 'foundto "bel fault'yythe sWi chB earl be.

steppedytherefromby Press .i :The circuits will Wh ena'n operator requires to find 'a' free trunk associatedwit-hm iree bye-passcireuit ing of.relay'PPfand"one-Wiper T o'ffthe switch to the byeqoass testjonduetor BET and searchesifor a'battery potentials; When the switch reaches a contact onwh'ich there is battery potential, the "relay PP -Will spies;-

atje opening the 'eireuit of thelmagnet-ltr The battery poten-tialfwillsignify thefree passucircuit the battery beingapplied over aviper K of the sWitehR2,home'cdntaot and I iper 8* of switch R1; $66, 67, Wiper 6 and 01 16 contact ofthe s'with R1,, 2561 981, bell v by -pass. test nd ctor BPT, Wiper Ten/ind? w g f herelay PP to ground at the key lheffnnotions oftheoontac ts in this circuit. will be discussedlater to show how the'loim .cuit Wonldlbe opened at any time while either the trunk and its switching device'- from -the 1 y p associated ptherewith 'isiin iis'e; The' portion of relay PP oloses'the' ei reuit for the relayHH from battery through thewinding' r.

key on. Re'lay clo'se's'its light Contact {hfil thereby making itself independentof r the relayPP. Earth is .extended fr'oini'keyj I O'Kiviaihhl, keyGK' hhBr-to Wiper-TQa-nd is i .l oriv bedeserib so 1 ingth e battery potential from BPT and subto prevent any further steps beingtaken when the relay PP releases. The lamp OL will I be lighted in multiple with the relay HH and I acts as a supervisory signal tothe operator.

sets of 10, whereas the bank contacts asso'cithat when the key is restored, the switch will ated with the contacts hh8 will have. every tenth contact multiple together. The oper- ,ator will insert the calling plug in themultiple jack OJ, which as has already beenexplained is extended direct to the bye-pass circuit and as a result dialling may'commence' immediately V V I I A relay'TB in the bye-pass circuit isoper- 'ated immediately the circuit is seized, removstituting earth potential to hold therelay and the operator may now restore key Contact hh4 extends ground to the test conductor H ofthe conversational path'and is required to enable the bye-pass switch R1 to find trunk in use. When'the bye-pass circuit is impulsedswitch R1 responds and switch R2 chasesso that the test circuit is further opened at wipers 6, 8 andK. The

switch Rlthen hunts inthe second part of its; banks for the trunk marked by ground v hasfoundthe outlet marked byithe switch "R2, a relay GS in the conversational trunk circult is operated so that contact 981 in the test circuit is opened. When the wanted line is found and tests free the relay GS is'released but a relay BS immediately operates,

re-operating. GS,"which locks up, and both I contacts 931, I981 are opened. The bye-pass circuit is then released and the switches home so that test potential is placed over tbl and the 981,581 contacts of idle trunks in the group which are now madea-vailable for use.

I Relay GS will remain operated until both subscribers have hung'upg I I I i In certain cases the operator may require a trunk in a particular group and this discrimr ination iseflected by means of'keyssuch as:

' A an-d' B which are used with the following V 'modificationto the wiring; the connection.

I marked X on the key OK is removed and the 'er'ators position, outgoing trunks terminatdotted connection from the key to wiper C is wired. The modification makes the testing circuit not only dependent upon the operation of the key'OK, and also'on the'position y of the wiper C. The bank contacts searched I over'by the wiper C are'arranged in groups correspondingtothe group of :the outlets.

All the bank contacts of each group being multipled together and connected 'to a key such as A or :B. By operatingthe key Afor instance simultaneously with the OK key, the operator will cause the trunk indicator switch to test only overthe'outlets 50f the describedgroup. 7

If an indicated trunk'is found to be faulty the switch can be stepped therefrom by. throwing a cancel key CK. This operation puts full earth on the switch magnet B so take a step forward. It will be appreciated that the key OK might becombinedwith the keys such as A, B, so that the'operator would onlyehave to throw'a singlekey'toobtain an indication of an available trunk in aparticular direction. E I

WVhatis claimedis :,.'f V r I 1. A telephone system comprising ancperators position," outgoing trunks terminating therein, conversational switches individual to said trunks, control apparatus associated in common withv a plurality of said'trunks and means adapted to identify an idletrunk.

in response-to potential applied over a circuit including normal contacts both of a free conversation switch and of a free control apparatus.

ators position, outgoing trunks terminating therein, conversation switches individual to 5 said trunks, control apparatus associated in common with'a pluralityv of said trunks, a hunting switchmeans'a'dapted to be actuated by the operator to cause said hunting switch to huntfor an idle'trunk which has access to an idleconversation switch and whichis associated with anidle control apparatus and means adaptedto be operated automatically inthe eventsaid idle trunk is faulty to step'the hunting switch forward on to another trunk.

2 wherein said means which is adapted to step the huntingswitch forwardupon being oper- 3. A telephone system according to claim ated closes'the circuit of the hunting switch and uponbeing released opens said circuit.

4. A telephone system comprising an operators position, outgoing trunks terminating -therein,conversation al switches individual to said trunks, bye-path circuits associated in common with a plurality of said trunksand means adapted tobe -actuated by the oper- "12.5

to an idle switch and associated with an idle ator toide'ntify oneof said trunks accessible bye-path circuit.v

5. A; telephonesystem, comprising an oping' therein, conversation switches individual 2. A telephone system comprising an oper l tosaid trunks, bye-path circuits associated in common with a plurality of said trunks, a hunting switch, means adapted to be actuated by the operator to cause saidhunting switch to hunt for an idle trunk whichhas access to an idle conversation switch and which is .associated with an idle control apparatus, and means whereby an. impulsing circuit is formed between the outgoing end of the selected trunkand the leads tothe bye-pathcir cuit over the said switch. I I

6. In a semi-automatic telephone system comprising a single control circuit associated in common with a group of conversational switches, adapted to control thesetting up of connections over any one of the latter in the case of circuit arrangements associated with which has access to an idle, conversation switch and. which is associated with an idle control apparatus and means adapted to iden tify saididle trunk in response to potential I applied over a circuit including normal contacts both of a free conversation'switch'and of a free controlapparatus.

my name.

an operators position at, which an indication individual toan idle trunk available for use by the operator may be given, and means whereby inresponse. to an action on the part of the operator an indication is given of a trunk individual to an idle conversational switch and an idle control circuit associate with the latter.

7. In a semi-automatic telephone system, i

the combination of a group of switches individual to a switching stage and each. associated and adapted to becontrolled by a com- I mon control circuit individual to the said 9; A telephone system comprising an op- V erators position, outgoing trunks terminating therein, conversation switches individual to said trunks, control apparatus associated in common with a plurality. of said trunks, a hunting switch, means adapted to be actuated by the operator to cause said hunt- I ing switch to hunt for an idle trunk which has access to an idle conversation switch and which is associated with an idlecontrol apparatus, and means adapted to identify an idle trunk in responseto potentialapplied over a circuit including normal contacts both of a .free conversation switch and of ajfree control apparatus.

101A telephone system comprising an opi erators position, a hunting switch,a plurali- 1 I 'ty of groups terminatingatsaidposition and in said switcln'conversational switches indi vidual to said trunks, control apparatus asso- 7 Q ciated in common with a. plurality of said trunks, means adapted to be actuated by the Operator to identify one of said pluralityof Q n'fwitness'whereof, I hereunto subscribe rs vlouo-rmLir-coonwm wRicHT.

groups of trunks and to cause said hunting switch to, hunt insaid group for anlidle trunk. 

